As shown in FIG. 10, a conventional tactile sensing array 6 (as disclosed in U.S. Pat. No. 4,492,949) includes a bottom layer 61, a middle layer 62 and a top layer 63 stacked on one another, and a plurality of longitudinally installed first conductors 64 are installed between the bottom layer 61 and the middle layer 62, and a plurality of transversally installed second conductors 65 are installed between the middle layer 62 and the top layer 63, and the middle layer 62 includes a plurality of conducting portions 66 in contact with the first and second conductors 64, 65 respectively, wherein the bottom layer 61, the middle layer 62 and the top layer 63 are flexible printed circuit boards, and the first and second conductors 64, 65 are made of a soft plastic material doped with conductors, such that the tactile sensing array 6 can be applied to a required device or apparatus. If a force is applied to the bottom layer 61 or the top layer 63, each conducting portion 66 on the middle layer 62 can be used for electrically connecting the first and second conductors 64, 65 for an electric transmission to achieve the tactile sensing effect.
The conventional tactile sensing array 6 adopts doped conductors, and thus the manufacturing cost is higher. Furthermore, the bottom layer 61, middle layer 62, top layer 63 and first and second conductors 64, 65 are limited to their materials and structures, so that the extensibility and elasticity of the tactile sensor 6 are lower, and the scope of applicability of the conventional tactile sensing array 6 becomes narrower, and it is relatively difficult to apply the conventional tactile sensor 6 to a complicated cambered surface. Since the first and second conductors 64, 65 are made of a soft plastic doped with conductors, a discontinuous contact between conductors may occur easily, so that the resistance of the first and second conductors 64, 65 becomes greater, or even a short circuit may result, due to the deformation.
Therefore, it is a major subject for the present invention to disclose a tactile sensing array and its manufacturing method, and the tactile sensing array has the effects of high extensibility, high elasticity and low manufacturing cost and prevents damages caused by high deformation when the tactile sensing array is used and covered onto a complicated surface.